A lonely paedophile who used computer games to lure in one of his intended victims has been jailed for two years.

Repeat offender Sean Doncaste, from Morden, had previously avoided jail for grooming children over the internet and was ordered not to contact anyone under 16 over the web in 2011.

But Doncaster ignored the ruling and escalated his behaviour by actually meeting one of his intended victims, a 15-year-old boy, in Beddington and buying him a computer game before asking for sexual favours in return.

Twenty-year-old Doncaster also pretended to be a girl on Facebook to approach three other children - one of them just 13-years-old - and encourage them to perform sex acts on video.

A judge branded him a "manipulative liar" before jailing him at Croydon Crown Court on Wednesday.

Doncaster, of Kirksted Road, started his offending in 2011 when he groomed a 12-year-old boy over internet chat service MSN Messenger and encouraged him to expose himself on a webcam.

He was convicted for the offence and was banned from contacting anyone under 16-years-old.

Just a week later he re-offended, this time approaching a 14-year-old boy over the Xbox Live computer game network and telling him he wanted to have sex with him.

In court he was spared jail and told it was his final chance.

Doncaster ignored the warning and, last year, approached three boys on Facebook and tried to get them to expose themselves by pretending to be a girl.

He also contacted a 15-year-old Sutton boy by playing Xbox Live games with him.

He befriended the boy and met him at Asda in Beddington Lane to buy him a computer game. He later invited his intended victim to go to the cinema so he could "suck him off".

The court heard the boy became concerned when his sister read about Doncaster's previous crimes, leading him to tell his parents.

Natalie Sherborn, defending Doncaster, said his crimes stemmed from isolation, low self esteem and his struggling to come to terms with being gay.

Judge Nicholas Ainley, sentencing, said: "I've listened to what has been said and it paints a disturbing picture of a manipulative liar who preys on young boys."